The present invention relates to machines which move over the field and form the cut crop into large cylindrical bales. One baling machine of this general type is shown in the U.S. Pat. No. 3,914,926 issued Oct. 28, l975 and which has been assigned to an assignee common with the present invention.
In such baling machines hay is received by the baler between a feed or packer roller and a conveyor belt and pressed into a flat, thin mass from which it passes to a core forming area where it is rolled between the conveyor belt and the flight of an oppositely moving belt arrangement. Thereafter, the thin mass of hay is rolled about the core into a bale which continues to increase in size until the desired size is achieved. During its formation, the bale is formed in a zone in which the bale is confined between the belts and the feeder roller.
In such balers the growing bale deflects and enlarges the length of the belt flight in the bale forming zone, and the increase in length must be accommodated by a mechanism which also serves to maintain the bale forming belt flight tight to apply compacting force to the bale.
The bale forming endless belt located generally in the upper part of the machine is commonly referred to as the containing belt means and consists of a plurality of side-by-side arranged individual belts which are trained around the supporting rollers. The tensioning of this upper belt means may be accomplished by the subject matter shown in the co-pending U.S. Pat. application Ser. No. 69,997, filed Aug. 27, 1979 and which has been assigned to an assignee common with the present invention.
Due to the fact that the rollers around which the containing belt means are trained are driven by two forces, that is they are driven by the containing belt means itself as well as being power driven by sprocket and chain means on occasion differential driving speeds are imparted to the rollers. In other words, the driving speed of the belt means and the sprocket and chain means is not always synchronized and in fact one varies from another depending on different circumstances such as dimensional tolerance differences in the roller diameters. The problem is particularly aggravated at that roller about which the wrap of the belt means is varied as the bale grows in size and also due to the fact that the pressure exerted by the bale being formed varies to cause varying pressure imparted to the bale means and against that particular roller. This prior art arrangement resulted in high horsepower requirements, excessive heating of the chains, over-loading of the belts due to the tension in them and excessive deflection loads on the roller shafts themselves.